Cybocephalus Erichson 1844

Cybocephalus Erichson 1844: 441-442.

 Redescription. Form: Ovate and very convex; body contractile (Fig. 4-2). Head:

Broad and deflexed. Labrum emarginate. Epistoma slightly prolonged at middle.

Mandibles in repose resting against metasternum, acute at tip with a small tooth

posteriorly. Maxillae with one lobe. Antennae slightly longer than width of head,

antennal club flat with 3 antennomeres, antennal grooves small and convergent. Scape

large and round. Thorax: Pronotum margined at base, covering base of elytra, sides very

short. Prostemum acutely carinate in front, not prolonged behind the procoxae, procoxal

cavities open behind. Mesostemum broad, oblique. Metasternum protuberant and

clothed in hairs. Both the meso- and metasternum are impressed for the reception of the

middle and hind legs. Scutellum: Large, triangular. Elytra: Covering or nearly covering

tip of the abdomen, apices curved. Abdomen: Five visible ventral plates (omitting the

small male anal plate), and 5 abdominal spiracles. Legs: Tibiae simple, tarsi four-

jointed, each tarsomere slightly dilated ventrally, second and third tarsomeres bilobed,

claws simple. Median lobe: Trunk heavily sclerotized and dorsoventrally compressed.

Tegmen: No parameres.

 Key to the species of Cybocephalus of America north of Mexico

1. Antennal club without a serrated margin (Fig. 4-12); scutellum with slightly
 concave margins (Fig. 4-11) ........ .. ................................ kathrynae new species

1'. Antennal club with a serrated margin (Fig. 4-4); scutellum with straight or slightly
 convex m argins (Fig. 4-10)........................................................... ............... 2

2(1') Terminal antennomere of the antennal club rounded (Fig. 4-30)..........................
 ...... .. .......... ............................... ..............randalli new species

2' Terminal antennomere of the antennal club truncate (Fig. 4-17) or slightly
 em arginate (Fig. 4-3, 4-4) .............................................. ...... .............